This research consists of a combined genetic, physiological, and biochemical characterization of two transport systems in Neurospora: (1) the primary H ion-translocating ATPase of the plasma membrane, which functions to generate a large H ion-electrochemical gradient; and (2) the H ion-dependent cotransport system for glucose, driven by the electrochemical gradient. During the next year, an attempt will be made to study ATP-linked H ion fluxes and H ion-linked glucose fluxes in isolated plasma membrane vesicles. In addition, we will continue to characterize a series of mutants (vanadate-resistant and deoxyglucose-resistant) which appear to be defective in transport. The results should contribute toward the understanding of transport mechanisms in eukaryotic cells generally.